Battery monomer, battery device, power utilization device and energy storage device

Abstract

The embodiment of the utility model provides a battery monomer, a battery device, a power utilization device and an energy storage device. The use performance of the battery monomer can be improved. The battery monomer comprises a shell, an electrode assembly and a first sealing structure, the shell comprises a first wall, the first wall is provided with a liquid injection hole penetrating through the first wall in the first direction, the electrode assembly is contained in the shell, the first sealing structure is in sealing connection with the liquid injection hole, and the first sealing structure comprises a groove with an opening deviating from the electrode assembly; the maximum outer diameter of the part, except the groove, of the first sealing structure is smaller than or equal to the minimum inner diameter of the liquid injection hole, the maximum outer diameter of the part, including the groove, of the first sealing structure is larger than the minimum inner diameter of the liquid injection hole, and the first direction is the direction along the thickness of the first wall and facing the electrode assembly.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of batteries, and more particularly, to a battery monomer, a battery device, a power utilization device and an energy storage device. BACKGROUND

[0002] Energy saving and emission reduction is the key to the sustainable development of the automobile industry. Electric vehicles have become an important part of the sustainable development of the automobile industry due to their energy saving and environmental protection advantages. For electric vehicles, battery technology is an important factor for their development.

[0003] In the assembly process of the battery monomer, it is usually necessary to seal the injection hole using a sealing structure after injection is completed. Under the condition of applying a large pressure to the sealing structure, the sealing structure may fall into the interior of the battery monomer, affecting the use performance and sealing performance of the battery monomer. Therefore, how to reduce the risk of the sealing structure falling into the interior of the battery monomer during the assembly process to improve the use performance of the battery monomer has become a technical problem to be solved in the field. UTILITY MODEL CONTENT

[0004] The embodiments of the present application provide a battery monomer, a battery device, a power utilization device and an energy storage device, which can improve the use performance of the battery monomer.

[0005] In a first aspect, the present application provides a battery monomer, comprising: a shell comprising a first wall, the first wall being provided with an injection hole penetrating through the first wall along a first direction; an electrode assembly accommodated in the interior of the shell; a first sealing structure in sealing connection with the injection hole, the first sealing structure comprising a groove with an opening facing away from the electrode assembly, the maximum outer diameter of the part of the first sealing structure other than the groove being less than or equal to the minimum inner diameter of the injection hole, the maximum outer diameter of the part of the first sealing structure including the groove being greater than the minimum inner diameter of the injection hole, and the first direction being the direction along the thickness of the first wall and towards the electrode assembly.

[0006] In the embodiments of the present application, the first sealing structure is arranged in the battery monomer, and the first sealing structure comprises a groove with an opening facing away from the electrode assembly, the maximum outer diameter of the part of the first sealing structure other than the groove being less than or equal to the minimum inner diameter of the injection hole, and the maximum outer diameter of the part of the first sealing structure including the groove being greater than the minimum inner diameter of the injection hole. Compared with the solid sealing structure in the prior art, the sealing connection between the first sealing structure and the injection hole is realized at the same time as the first sealing structure is assembled to the injection hole, the assembly of the first sealing structure is facilitated, the sealing effect at the injection hole of the battery monomer is improved, and thus the use performance and assembly performance of the battery monomer are improved.

[0007] In some embodiments, the first sealing structure comprises a first portion and a second portion distributed along the first direction, the second portion being located on a side of the first portion facing the electrode assembly, wherein the first portion comprises a through hole penetrating through the first portion along the first direction, the second portion comprises a counterbore facing away from the electrode assembly, the through hole and the counterbore are in communication to form the groove, at least part of the second portion is accommodated in the liquid injection hole and is in sealed connection with the liquid injection hole, the maximum inner diameter D2 of the counterbore is greater than the maximum inner diameter D1 of the through hole, and the maximum outer diameter D3 of the second portion is less than or equal to the minimum inner diameter D4 of the liquid injection hole.

[0008] In the embodiments of the present application, by setting the first sealing structure to comprise a first portion and a second portion distributed along the first direction, the second portion being located on a side of the first portion facing the electrode assembly, and setting the first portion to comprise a through hole penetrating through the first portion along the first direction, and setting the second portion to comprise a counterbore facing away from the electrode assembly, the through hole and the counterbore are in communication to form the groove, at least part of the second portion is accommodated in the liquid injection hole and is in sealed connection with the liquid injection hole, the maximum inner diameter D2 of the counterbore is greater than the maximum inner diameter D1 of the through hole, and the maximum outer diameter D3 of the second portion is less than or equal to the minimum inner diameter D4 of the liquid injection hole, that is, at least part of the second portion can be smoothly accommodated in the liquid injection hole and in sealed connection with the liquid injection hole during assembly of the first sealing structure to the liquid injection hole, and the first portion can limit the first sealing structure, thereby reducing the risk of the first sealing structure falling off or falling into the interior of the battery monomer, thereby improving the assembly performance and use performance of the battery monomer, and the structure design is simple, facilitating processing and manufacturing of the battery monomer.

[0009] In some embodiments, the difference between the maximum outer diameter D3 of the second portion and the minimum inner diameter d2 of the counterbore is less than the minimum inner diameter D4 of the liquid injection hole. In this way, in the embodiments of the present application, by setting the difference between the maximum outer diameter D3 of the second portion and the minimum inner diameter d2 of the counterbore to be less than the minimum inner diameter D4 of the liquid injection hole, at least part of the second portion can be smoothly accommodated in the liquid injection hole during assembly of the first sealing structure, reducing the force applied to the first sealing structure during assembly, thereby improving the assembly performance and use performance of the battery monomer.

[0010] In some embodiments, a difference between the maximum outer diameter D5 of the first portion and the maximum inner diameter D1 of the through hole is greater than the minimum inner diameter D4 of the liquid injection hole. In this way, in the embodiments of the present application, by setting the difference between the maximum outer diameter D5 of the first portion and the maximum inner diameter D1 of the through hole to be greater than the minimum inner diameter D4 of the liquid injection hole, in the process of assembling the first sealing structure, at least part of the second portion is accommodated in the liquid injection hole, the first portion can effectively play a limiting role on the first sealing structure, so as to further reduce the risk of the first sealing structure falling off or falling into the inside of the battery monomer, thereby improving the assembly performance and use performance of the battery monomer.

[0011] In some embodiments, the first sealing structure further comprises a third portion arranged on the side of the second portion facing the electrode assembly, a projection of the second portion covers a projection of the third portion in a plane perpendicular to the first direction, and an outer diameter of the third portion gradually decreases along the first direction.

[0012] In the embodiments of the present application, by arranging the first sealing structure to include a third portion connected to the side of the second portion facing the electrode assembly, and the projection of the second portion covers the projection of the third portion in a plane perpendicular to the first direction, and the outer diameter of the third portion gradually decreases along the first direction, so as to smoothly accommodate part of the first sealing structure inside the liquid injection hole, effectively reduce the force applied to the first sealing structure during assembly, thereby improving the assembly performance and use performance of the battery monomer.

[0013] In some embodiments, the surface of the first sealing structure away from the electrode assembly is lower than the surface of the first wall away from the electrode assembly, or the surface of the first sealing structure away from the electrode assembly is flush with the surface of the first wall away from the electrode assembly.

[0014] In the embodiments of the present application, by arranging the surface of the first sealing structure away from the electrode assembly to be lower than the surface of the first wall away from the electrode assembly, or arranging the surface of the first sealing structure away from the electrode assembly to be flush with the surface of the first wall away from the electrode assembly, to reduce the collision or wear of the first sealing structure during assembly or movement of the battery monomer, improve the sealing performance of the first sealing structure, thereby improving the use performance of the battery monomer.

[0015] In some embodiments, the inner diameter of the liquid injection hole gradually decreases along the first direction. In this way, in the embodiments of the present application, by setting the inner diameter of the liquid injection hole along the first direction to gradually decrease, the structure of the liquid injection hole can effectively limit the first sealing structure during assembly of the first sealing structure, further reducing the risk of the first sealing structure falling off or falling into the interior of the battery monomer, thereby improving the assembly performance and use performance of the battery monomer, and the structural design of the liquid injection hole is simple, facilitating the processing and manufacturing of the battery monomer.

[0016] In some embodiments, the first part and the second part are integrally formed. In this way, in the embodiments of the present application, by setting the first part and the second part to be integrally formed, the sealing performance and assembly performance of the first sealing structure can be effectively improved, thereby improving the use performance of the battery monomer, and facilitating the reduction of the processing and manufacturing cost of the battery monomer.

[0017] In some embodiments, the battery monomer further comprises a second sealing structure, the second sealing structure is in sealing connection with the liquid injection hole, the second sealing structure is located on the side of the first sealing structure away from the electrode assembly, and the second sealing structure is in fixed connection with the first sealing structure, wherein the projection of the second sealing structure covers the projection of the first sealing structure in the plane perpendicular to the first direction.

[0018] In the embodiments of the present application, by setting the second sealing structure in the battery monomer, the second sealing structure is in sealing connection with the liquid injection hole, the second sealing structure is located on the side of the first sealing structure away from the electrode assembly, and the projection of the second sealing structure covers the projection of the first sealing structure in the plane perpendicular to the first direction, thereby further improving the limiting effect of the first sealing structure, further reducing the risk of the first sealing structure falling off or falling into the interior of the battery monomer, thereby improving the assembly performance and use performance of the battery monomer, and the second sealing structure is in fixed connection with the first sealing structure, which can improve the assembly efficiency of the first sealing structure and the second sealing structure relative to the liquid injection hole.

[0019] In some embodiments, the second sealing structure comprises a main body part and a protruding part, the protruding part is arranged on the surface of the main body part on the side facing the electrode assembly, and the protruding part and the inner wall of the groove are connected by one of the following connection modes: threaded connection, clamping connection or interference connection.

[0020] In the embodiment of the present application, the second sealing structure is provided with a main body and a protruding portion, and the protruding portion is arranged on the surface of the main body facing the electrode assembly. The protruding portion and the inner wall of the groove are connected by one of the following connection modes: threaded connection, clamping connection or interference fit. The connection strength between the second sealing structure and the first sealing structure is improved to effectively improve the assembly efficiency of the second sealing structure and the first sealing structure relative to the liquid injection hole, thereby effectively improving the limiting effect of the first sealing structure, reducing the risk of the first sealing structure falling off or falling into the interior of the battery monomer, and improving the assembly performance and use performance of the battery monomer.

[0021] In some embodiments, the protruding portion is threadedly connected with the inner wall of the through hole. In this way, in the embodiment of the present application, the protruding portion and the inner wall of the through hole are threadedly connected to improve the assembly efficiency of the second sealing structure and the first sealing structure relative to the liquid injection hole, thereby effectively improving the limiting effect of the first sealing structure, further reducing the risk of the first sealing structure falling off or falling into the interior of the battery monomer, and improving the assembly performance and use performance of the battery monomer. The connection mode is simple and efficient, and can reduce the processing and manufacturing cost of the battery monomer.

[0022] In some embodiments, the liquid injection hole includes a first hole section and a second hole section distributed along the first direction, the first hole section is located on the side of the second hole section away from the electrode assembly, the aperture of the first hole section is larger than the aperture of the second hole section, part of the second sealing structure is accommodated in the first hole section, and at least part of the first sealing structure is accommodated in the second hole section.

[0023] In the embodiment of the present application, the first hole section and the second hole section are arranged in the liquid injection hole along the first direction, the aperture of the first hole section is larger than the aperture of the second hole section, part of the second sealing structure is accommodated in the first hole section, and at least part of the first sealing structure is accommodated in the second hole section, so as to facilitate the assembly efficiency of the second sealing structure and the first sealing structure relative to the liquid injection hole, thereby improving the assembly performance and use performance of the battery monomer.

[0024] In some embodiments, the liquid injection hole further includes a flat section arranged between the first hole section and the second hole section, and the first sealing structure further includes an extension portion arranged on the outer periphery of the first sealing structure, the extension portion extends away from the geometric center of the first sealing structure, and the surface of the extension portion facing the electrode assembly is attached to the surface of the flat section away from the electrode assembly.

[0025] In the embodiments of the present application, the first sealing structure further comprises an extension part arranged on the outer periphery of the first sealing structure, the extension part extends away from the geometric center of the first sealing structure, and the surface of the extension part on the side away from the electrode assembly is attached to the surface of the flat section on the side away from the electrode assembly, so as to improve the limiting effect of the first sealing structure, further reduce the risk of the first sealing structure falling off or falling into the interior of the battery monomer, and thus improve the assembly performance and use performance of the battery monomer.

[0026] In some embodiments, the size of the protruding part is less than or equal to the depth of the groove in the first direction. In this way, in the embodiments of the present application, by setting the size of the protruding part to be less than or equal to the depth of the groove, the protruding part can be accommodated in the groove, that is, the surface of the main body part on the side away from the electrode assembly can be attached to the surface of the extension part on the side away from the electrode assembly, so as to improve the connection strength between the first sealing structure and the second sealing structure, facilitate the assembly efficiency of the second sealing structure relative to the first sealing structure with respect to the liquid injection hole, and thus improve the assembly performance and use performance of the battery monomer.

[0027] In some embodiments, the surface of the second sealing structure on the side away from the electrode assembly is lower than the surface of the first wall on the side away from the electrode assembly, or the surface of the second sealing structure on the side away from the electrode assembly is flush with the surface of the first wall on the side away from the electrode assembly.

[0028] In the embodiments of the present application, by setting the surface of the second sealing structure on the side away from the electrode assembly to be lower than the surface of the first wall on the side away from the electrode assembly, or setting the surface of the second sealing structure on the side away from the electrode assembly to be flush with the surface of the first wall on the side away from the electrode assembly, the collision or wear of the second sealing structure during assembly or movement of the battery monomer is reduced, the sealing performance of the second sealing structure is improved, and thus the use performance of the battery monomer is improved.

[0029] In a second aspect, a battery device is provided, comprising: a plurality of battery monomers, the battery monomers being the battery monomers in the first aspect or any implementation manner thereof.

[0030] In a third aspect, a power consuming device is provided, comprising the battery device in the first aspect, and the battery device is used to provide electric energy for the power consuming device.

[0031] In some implementations, the power consuming device can be a vehicle, a ship, a spacecraft, or the like.

[0032] In a fourth aspect, there is provided an energy storage device comprising the battery device of the second aspect, the battery device being configured to store electrical energy for the energy storage device. BRIEF DESCRIPTION OF DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments of the present application will be briefly introduced as follows. Obviously, the drawings described below are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of the drawings.

[0034] Figure 1 is a structural schematic diagram of a vehicle provided by an embodiment of the present application.

[0035] Figure 2 is a structural schematic diagram of a battery device provided by an embodiment of the present application.

[0036] Figure 3 is an exploded structural schematic diagram of a battery cell provided by an embodiment of the present application.

[0037] Figure 4 is an exploded structural schematic diagram of a battery cell provided by another embodiment of the present application.

[0038] Figure 5 is a cross-sectional schematic diagram of a battery cell provided by an embodiment of the present application.

[0039] Figure 6 is a partially enlarged cross-sectional schematic diagram of a battery cell provided by an embodiment of the present application.

[0040] Figure 7 is a cross-sectional schematic diagram of a first sealing structure provided by another embodiment of the present application.

[0041] Figure 8 is a partially enlarged cross-sectional schematic diagram of a battery cell provided by another embodiment of the present application.

[0042] Figure 9 is a partially enlarged cross-sectional schematic diagram of a battery cell provided by yet another embodiment of the present application.

[0043] Figure 10 is a partially enlarged cross-sectional schematic diagram of a battery cell provided by yet another embodiment of the present application.

[0044] Explanation of reference numerals: 1 - vehicle; 10 - battery device; 20 - battery cell; 30 - controller; 40 - motor; 11 - case; 111 - first structure; 112 - second structure; 112a - bottom plate; 112b - side plate; 21 - outer case; 22 - electrode assembly; 211 - case; 212 - end cap; 213 - pressure relief mechanism; 222 - tab; 222a - positive electrode tab; 222b - negative electrode tab; 214 - electrode terminal; 214a - positive electrode terminal; 214b - negative electrode terminal; 23 - connecting member; 215 - first wall; 216 - liquid injection hole; 217 - first hole section; 218 - second hole section; 219 - flat section; 50 - first sealing structure; 510 - groove; 520 - first portion; 521 - through hole; 530 - second portion; 531 - counterbore; 540 - third portion; 550 - extension; 60 - second sealing structure; 610 - main body portion; 620 - protruding portion.

[0045] In the drawings, the drawings are not drawn according to the actual proportions. DETAILED DESCRIPTION

[0046] The technical solutions in the embodiments of the present application will be described below with reference to the drawings.

[0047] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly below with reference to the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0048] Unless otherwise defined, all technical and scientific terms used in the present application have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs; the terms used in the specification of the present application are only for the purpose of describing the specific embodiments of the present application, and are not intended to limit the present application; the terms "include" and "have" and any variations thereof in the specification and claims of the present application and the above description of drawings are intended to cover non-exclusive inclusion. The terms "first", "second" and the like in the specification and claims of the present application and the above description of drawings are used to distinguish different objects, and are not intended to describe a specific order or primary and secondary relationship.

[0049] Reference to an "embodiment" in this application means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily mutually exclusive of one another. It is expressly understood that that the embodiments described in this application can be combined with each other in their various permutations and combinations.

[0050] In the description of the application, it is necessary to explain that, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting", "attachment" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral connection; it can be direct connection, or indirect connection through intermediate medium, or internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0051] In this application, the term "and / or" is only a description of the association relationship between the associated objects, which means that there can be three kinds of relationships, for example, A and / or B can represent the following three cases: A exists alone, A and B exist together, and B exists alone. In addition, the character " / " in this application generally represents an "or" relationship between the associated objects before and after it.

[0052] In the embodiments of the application, the same reference signs represent the same components, and for the sake of brevity, the detailed description of the same components is omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device, are only exemplary and should not constitute any limitation on the application.

[0053] "Multiple" appearing in this application means more than two (including two), and similarly, "multiple groups" means more than two groups (including two groups), and "multiple pieces" means more than two pieces (including two pieces).

[0054] If not specifically stated, all embodiments and optional embodiments of the application can be combined with each other to form new technical solutions.

[0055] If not specifically stated, all technical features and optional technical features of the application can be combined with each other to form new technical solutions.

[0056] In some embodiments, the positive electrode can be a positive electrode sheet, which can include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0057] As an example, the positive electrode current collector has two surfaces opposite in the thickness direction thereof, and the positive electrode active material is provided on either one or both of the two surfaces of the positive electrode current collector.

[0058] As an example, the positive electrode current collector can employ a metal foil, a conductive polymer material, a carbon material, or a composite current collector. For example, as the metal foil, a pure metal, an alloy, a surface-treated metal, including but not limited to stainless steel, copper, aluminum, nickel, nickel, titanium, or silver, and the like can be employed. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, and the like) on a polymer material base material (such as a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, and the like).

[0059] In some embodiments, the positive electrode can employ a foam metal. The foam metal can be a foam nickel, a foam copper, a foam aluminum, a foam alloy, or a foam carbon, and the like. When the foam metal is employed as the positive electrode, the foam metal surface can not be provided with the positive electrode active material, and of course, can be provided with the positive electrode active material. As an example, the positive electrode active material is filled or / and deposited within the foam metal.

[0060] In some embodiments, the negative electrode can be a negative electrode sheet, which can include a negative electrode current collector.

[0061] As an example, the negative electrode current collector can employ a metal foil, a conductive polymer material, a carbon material, or a composite current collector. For example, as the metal foil, a pure metal, an alloy, a surface-treated metal, including but not limited to stainless steel, copper, aluminum, nickel, nickel, titanium, or silver, and the like can be employed. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, and the like) on a polymer material base material (such as a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, and the like).

[0062] As an example, the negative electrode sheet can include the negative electrode current collector and the negative electrode active material provided on at least one surface of the negative electrode current collector.

[0063] As an example, the negative electrode current collector has two surfaces opposite in the thickness direction thereof, and the negative electrode active material is provided on either one or both of the two surfaces of the negative electrode current collector.

[0064] As an example, the negative active material can employ a negative active material for a battery cell known in the art. As an example, the negative active material can include at least one of artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based material, tin-based material, and lithium titanate, etc. The silicon-based material can be selected from at least one of elemental silicon, silicon oxide compound, silicon-carbon composite, silicon-nitrogen composite, and silicon alloy. The tin-based material can be selected from at least one of elemental tin, tin oxide compound, and tin alloy. However, the present application is not limited to these materials, and other conventional materials that can be used as a negative active material for a battery cell can also be used. These negative active materials can be used alone or in combination of two or more.

[0065] In some embodiments, the negative electrode can employ a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. When the foamed metal is used as a negative electrode sheet, the foamed metal surface can not be provided with a negative active material, or can be provided with a negative active material.

[0066] As an example, the negative active material can be filled or / and deposited in the negative current collector.

[0067] In some embodiments, the material of the positive current collector can be aluminum, and the material of the negative current collector can be copper.

[0068] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.

[0069] In some embodiments, the separator is a separator film. The present application does not particularly limit the type of the separator film, and any known porous structure separator film having good chemical stability and mechanical stability can be used.

[0070] As an example, the main material of the separator film can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride, and ceramic. The separator film can be a single layer film or a multi-layer composite film, and is not particularly limited. When the separator film is a multi-layer composite film, the materials of the respective layers can be the same or different, and are not particularly limited. The separator can be a separate component located between the positive and negative electrodes, or can be attached to the surface of the positive and negative electrodes. An inorganic particle coating layer, an organic particle coating layer, or an organic / inorganic composite coating layer can be applied to the surface of the separator film.

[0071] In some embodiments, the separator is a solid-state electrolyte. The solid-state electrolyte is disposed between the positive electrode and the negative electrode, and functions to transport ions and separate the positive and negative electrodes.

[0072] In some embodiments, the battery cell further comprises an electrolyte, which functions to conduct ions between the positive and negative electrodes. The type of electrolyte is not specifically limited in the present application and can be selected as needed. The electrolyte can be liquid, gel, or solid.

[0073] In some embodiments, the electrolyte is a liquid electrolyte. The liquid electrolyte can comprise an electrolyte salt and a solvent.

[0074] In some embodiments, the electrolyte can further optionally comprise an additive. For example, the additive can comprise a negative electrode film-forming additive, a positive electrode film-forming additive, or an additive capable of improving certain properties of the battery cell, such as an additive capable of improving overcharge / fast charge performance, an additive capable of improving high-temperature performance, an additive capable of improving low-temperature performance, and the like.

[0075] In some embodiments, the electrolyte is a gel electrolyte. The gel electrolyte can comprise a polymer as a backbone network and can be used in combination with an ionic liquid-lithium salt.

[0076] In some embodiments, the electrolyte is a solid electrolyte. The solid electrolyte can comprise a polymer solid electrolyte, an inorganic solid electrolyte, or a composite solid electrolyte.

[0077] As an example, the polymer of the polymer solid electrolyte can comprise a polyether (polyethylene oxide), a polysiloxane, a polycarbonate, a polyacrylonitrile, a polyvinylidene fluoride, a polymethyl methacrylate, a single-ion polymer, a polyionic liquid, cellulose, or the like.

[0078] As an example, the inorganic solid electrolyte can be one or more of an oxide solid electrolyte (crystalline perovskite, sodium superionic conductor, garnet, amorphous LiPON thin film), a sulfide solid electrolyte (crystalline lithium superionic conductor (lithium germanium phosphorus sulfide, argyrodite), amorphous sulfide), a halide solid electrolyte, a nitride solid electrolyte, and a hydride solid electrolyte.

[0079] As an example, the composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0080] The electrode assembly can be a wound structure, a stacked structure, or a hybrid structure of a wound and stacked structure.

[0081] In some embodiments, the electrode assembly is a wound structure. The positive electrode sheet and the negative electrode sheet are wound into a wound structure.

[0082] In some embodiments, the electrode assembly is a stacked structure.

[0083] As an example, a plurality of positive electrode sheets and a plurality of negative electrode sheets can be provided, and the plurality of positive electrode sheets and the plurality of negative electrode sheets can be alternately stacked.

[0084] As an example, the positive electrode sheet can be provided in a plurality of pieces, and the negative electrode sheet can be folded to form a plurality of folded sections arranged in layers.

[0085] As an example, the positive electrode sheet and the negative electrode sheet can each be folded to form a plurality of folded sections arranged in layers.

[0086] As an example, a plurality of separators can be provided, each provided between any adjacent positive electrode sheet or negative electrode sheet.

[0087] As an example, a separator can be provided continuously between any adjacent positive electrode sheet or negative electrode sheet by folding or winding.

[0088] In some embodiments, the electrode assembly can have a cylindrical shape, a flat shape, or a polygonal shape.

[0089] In some embodiments, the electrode assembly can be provided with a tab, which can guide current out of the electrode assembly. The tab can include a positive tab and a negative tab.

[0090] In some embodiments, the battery cell can include a housing. The housing can be a steel housing, an aluminum housing, a plastic housing (e.g., a polypropylene housing), a composite metal housing (e.g., a copper-aluminum composite housing), or an aluminum-plastic film, etc. In some embodiments, the housing can be a sealed structure or a non-sealed structure. As an example, when the housing is a non-sealed structure, the housing serves to protect the electrode assembly, and a sealing bag can be further included between the housing and the electrode assembly, the sealing bag being configured to encapsulate the electrode assembly and an electrolyte. Specifically, the sealing bag can be a bag-shaped insulating member or an aluminum-plastic film. When the housing is a sealed structure, the housing is configured to encapsulate the electrode assembly and the electrolyte.

[0091] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell having another shape. The prismatic battery cell can include a square battery cell, a blade battery cell, a polygonal battery cell (e.g., a hexagonal battery cell), etc.

[0092] In some embodiments, at least one electrode terminal can be provided on the housing, and the electrode terminal can be electrically connected to the tab. The electrode terminal can be directly connected to the tab or indirectly connected to the tab via a current collector. The electrode terminal can be provided on an end cap or on the housing.

[0093] In some embodiments, a pressure relief mechanism can be provided on the housing. The pressure relief mechanism can be configured to discharge internal gas of the battery cell.

[0094] As an example, the internal pressure or temperature of the battery cell reaches a predetermined threshold value, and the pressure relief mechanism is actuated to release the internal pressure or temperature. When the internal pressure or temperature of the battery cell reaches the predetermined threshold value, the pressure relief mechanism performs an action or a weak structure provided in the pressure relief mechanism is broken, thereby forming an opening or a passage for the internal pressure or temperature to be released. The threshold value is designed differently according to design requirements. The threshold value can depend on the material of one or more of the positive plate, the negative plate, the electrolyte, and the separator in the battery cell.

[0095] As an example, the pressure relief mechanism can be integrally formed with the housing.

[0096] As an example, the pressure relief mechanism can also be provided separately from the housing and connected.

[0097] As used herein, "actuation" refers to the pressure relief mechanism performing an action or being activated to a certain state, thereby allowing the internal pressure and temperature of the battery cell to be released. The action performed by the pressure relief mechanism can include, but is not limited to, a component in the pressure relief mechanism moving to form an exhaust passage, at least a portion of the pressure relief mechanism breaking, shattering, being torn or opened, and the like. When the pressure relief mechanism is actuated, the high-temperature and high-pressure substances inside the battery cell are discharged as exhaust from the actuated part. In this way, the battery cell can be released at a controllable pressure or temperature, thereby avoiding potential more serious accidents.

[0098] In some embodiments, when the housing is a non-sealed structure, the pressure relief mechanism can be provided as a through hole for discharging the gas inside the battery cell.

[0099] As used herein, the exhaust from the battery cell includes, but is not limited to, electrolyte, dissolved or split positive and negative plates, fragments of the separator, high-temperature and high-pressure gas generated by the reaction, flame, and the like.

[0100] The battery device as referred to in the embodiments of the present application can include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly can include a plurality of battery cells connected in series, in parallel, or in a mixed connection through a busbar.

[0101] In some embodiments, the battery cell assembly is generally formed by arranging a plurality of battery cells.

[0102] As an example, the battery cell assembly can be a battery module formed by arranging and fixing a plurality of battery cells into an independent module. As an example, the battery module can be formed by bundling a plurality of battery cells with a cable tie.

[0103] In some embodiments, the battery device can be a battery pack including a box and one or more battery cell assemblies accommodated in the box.

[0104] As an example, the battery cell assembly can be a battery module, and the battery cell assembly can be accommodated in the case by fixing the battery module in the case.

[0105] As an example, the battery cell assembly can also be accommodated in the case by fixing a plurality of battery cells directly in the case.

[0106] As an example, the case can include a first case and a second case. The first case and the second case are fastened so that an enclosed space is formed inside the case to accommodate the battery cell assembly. Here, the enclosed means covered or closed, which can be sealed or unsealed. The first case can be a top cover or a bottom plate.

[0107] As an example, the case can include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are connected to the frame, respectively, so that an enclosed space is formed inside the case to accommodate the battery cell assembly.

[0108] In some embodiments, the case can be part of a chassis structure of a vehicle. For example, part of the case can be at least part of a floor of the vehicle, or part of the case can be at least part of a cross beam and a longitudinal beam of the vehicle.

[0109] The technical solutions described in the embodiments of the present application are applicable to various electric devices using battery cells, such as mobile phones, portable devices, notebook computers, electric vehicles, electric toys, electric tools, vehicles, ships, and spacecraft, such as aircraft, rockets, space shuttles, and spacecraft.

[0110] The embodiments of the present application provide a power storage device including one or more battery clusters to improve the voltage and capacity of the power storage device. The battery cluster can include a plurality of battery devices connected in series by a busbar component to improve the voltage of the power storage device. When the power storage device includes a plurality of battery clusters, the plurality of battery clusters are connected in parallel to improve the capacity of the power storage device.

[0111] The power storage device can be used in a power storage power station, a wind power generation system, a solar power generation system, a mobile power system, or a temporary power supply system, etc. The power storage device can store electrical energy as needed and output electrical energy at an appropriate time. For example, the power storage device can store electrical energy during a low electricity usage period and provide electrical energy to related users or electric devices during a high electricity usage period. The power storage system provided by the embodiments of the present application can be any power system that needs to use a power storage device.

[0112] In some embodiments, the power storage device is a power storage container or a power storage cabinet.

[0113] In some embodiments, the power storage device can include a cabinet body and one or more battery clusters, and the battery clusters are accommodated in the cabinet body.

[0114] In some embodiments, the energy storage device can include a thermal management module, a master control module, a general control module, a power distribution module, a fire control module, and the like.

[0115] As an example, the thermal management module can include a liquid cooling unit that provides cooling liquid to each battery device through a pipeline for adjusting the temperature of the battery monomer.

[0116] As an example, the master control module can serve as a battery management unit of the battery cluster for monitoring and managing the battery cluster. The master control module can monitor information such as current, voltage, power, or temperature of the battery cluster. For example, the charging and discharging current, voltage, and the like of the battery cluster can be controlled. The master control module includes an auxiliary battery management unit, a fusion switch, and the like.

[0117] As an example, the general control module can serve as a battery management unit of the energy storage device for monitoring and managing the energy storage device. The general control module can monitor information such as current, voltage, power, state of charge, or temperature of the energy storage device. For example, the charging and discharging current, voltage, and the like of the energy storage device can be controlled. As an example, the general control module includes an insulation monitoring module, a main battery management unit, an Ethernet and optical fiber conversion module, and the like.

[0118] As an example, the fire control system includes a control panel, a detector, an alarm device, and the like for detecting, alarming, or extinguishing the energy storage system.

[0119] As an example, the power distribution device can be used to distribute power to the energy storage device power module.

[0120] Energy saving and emission reduction is the key to the sustainable development of the automobile industry. Electric vehicles have become an important part of the sustainable development of the automobile industry due to their energy-saving and environmentally friendly advantages. For electric vehicles, battery technology is an important factor for their development. At present, in the assembly process of the battery monomer, it is usually necessary to seal the injection hole using a sealing structure after injection is completed. Under the condition of applying a relatively large pressure to the sealing structure, the sealing structure may fall or slide into the interior of the battery monomer, which is easy to cause the performance of the battery monomer to fail or to cause the phenomenon of swelling, affecting the use performance and sealing performance of the battery monomer. Therefore, how to reduce the risk of the sealing structure falling into the interior of the battery monomer during the assembly process to improve the use performance of the battery monomer has become a technical problem to be solved in the field.

[0121] Therefore, the battery monomer, the battery device, the power utilization device and the energy storage device are provided, the battery monomer comprises: a shell, an electrode assembly and a first sealing structure, the shell comprises a first wall, the first wall is provided with a liquid injection hole penetrating through the first wall along a first direction, the electrode assembly is contained in the inside of the shell, the first sealing structure is in sealing connection with the liquid injection hole, the first sealing structure comprises a groove with an opening facing away from the electrode assembly, the maximum outer diameter of the part of the first sealing structure except the groove is less than or equal to the minimum inner diameter of the liquid injection hole, and the maximum outer diameter of the part of the first sealing structure including the groove is greater than the minimum inner diameter of the liquid injection hole, and the first direction is the direction along the thickness of the first wall and towards the electrode assembly. In this way, in the embodiments of the present application, by providing the first sealing structure in the battery monomer, and the first sealing structure comprises a groove with an opening facing away from the electrode assembly, the maximum outer diameter of the part of the first sealing structure except the groove is less than or equal to the minimum inner diameter of the liquid injection hole, and the maximum outer diameter of the part of the first sealing structure including the groove is greater than the minimum inner diameter of the liquid injection hole, compared with the solid sealing structure in the prior art, so as to facilitate the sealing connection between the first sealing structure and the liquid injection hole while assembling the first sealing structure to the liquid injection hole, facilitate the assembly of the first sealing structure, improve the sealing effect at the liquid injection hole of the battery monomer, and thus improve the use performance and assembly performance of the battery monomer.

[0122] The technical solutions described in the embodiments of the present application are applicable to various power utilization devices using battery devices.

[0123] The power utilization device can be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy and an electric tool, etc. The vehicle can be a fuel automobile, a gas automobile or a new energy automobile, and the new energy automobile can be a pure electric automobile, a hybrid electric automobile or a range extended automobile, etc. The spacecraft includes an airplane, a rocket, a space shuttle and a spacecraft, etc. The electric toy includes a fixed or mobile electric toy, for example, a game machine, an electric automobile toy, an electric ship toy and an electric airplane toy, etc. The electric tool includes a metal cutting electric tool, a grinding electric tool, an assembling electric tool and a railway electric tool, for example, an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact electric drill, a concrete vibrator and an electric planer, etc. The embodiments of the present application do not specially limit the above-mentioned power utilization devices.

[0124] It should be understood that the technical solutions described in the embodiments of the present application are not only limited to the above-mentioned power utilization devices, but also applicable to all devices using batteries. The following embodiments will be described in detail taking the vehicle as an example for brevity.

[0125] For example, as Figure 1The diagram shown is a structural schematic of a vehicle 1 according to one embodiment of this application. Vehicle 1 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A motor 40, a controller 30, and a battery device 10 can be installed inside vehicle 1. The controller 30 controls the battery device 10 to supply power to the motor 40. For example, the battery device 10 can be installed at the bottom, front, or rear of vehicle 1. The battery device 10 can be used to power vehicle 1. For example, the battery device 10 can serve as the operating power source for vehicle 1, for example, to meet the electrical system requirements of vehicle 1, such as for starting, navigation, and operation. In another embodiment of this application, the battery device 10 can not only serve as the operating power source for vehicle 1, but also as the driving power source for vehicle 1, replacing or partially replacing gasoline or natural gas to provide driving power for vehicle 1.

[0126] To meet different power demands, the battery device 10 in this embodiment may include at least one battery cell assembly, which comprises multiple battery cells. These multiple battery cells can be electrically connected in series, parallel, or a combination thereof to form the battery device 10. A combination of series and parallel connections is used. The battery device 10 may also be referred to as a battery pack. For example, multiple battery cells can first be connected in series, parallel, or a combination to form a battery module, and then multiple battery modules can be connected in series, parallel, or a combination thereof to form the battery device 10. That is, multiple battery cells can directly form the battery device 10, or they can first be assembled into battery modules, and then the battery modules can be assembled into the battery device 10.

[0127] For example, such as Figure 2 The diagram shown is a structural schematic of a battery device 10 according to an embodiment of this application. The battery device 10 may include a plurality of battery cells 20. The battery device 10 may also include a housing 11 (or cover), the housing 11 having a hollow structure, and the plurality of battery cells 20 are housed within the housing 11. For example, the plurality of battery cells 20 may be connected in parallel, in series, or in a mixed configuration and then placed within the housing 11.

[0128] like Figure 2As shown, the box 11 can include two parts, here referred to as a first structure 111 and a second structure 112, which are buckled together. The shapes of the first structure 111 and the second structure 112 can be determined according to the shape of the combination of the plurality of battery monomers 20, and the first structure 111 and the second structure 112 can each have an opening. For example, the first structure 111 and the second structure 112 can each be a hollow cuboid and each have only one face as an opening face, the opening of the first structure 111 and the opening of the second structure 112 are oppositely arranged, and the first structure 111 and the second structure 112 are buckled to each other to form a box 11 with a closed cavity. Among them, the second structure 112 can include a bottom plate 112a, a side plate 112b and a beam. The plurality of battery monomers 20 are combined in parallel or in series or in a hybrid manner and placed in the box 11 formed after the buckling of the first structure 111 and the second structure 112.

[0129] Optionally, the battery device 10 can also include other structures, which will not be described one by one here. For example, the battery device 10 can also include a current collecting component for realizing the electrical connection between the plurality of battery monomers 20, such as parallel connection, series connection or hybrid connection. Specifically, the current collecting component can realize the electrical connection between the battery monomers 20 by connecting the electrode terminals of the battery monomers 20. Further, the current collecting component can be fixed to the electrode terminals of the battery monomers 20 by welding. The electrical energy of the plurality of battery monomers 20 can be further led out through the box by a conductive mechanism. Optionally, the conductive mechanism can also belong to the current collecting component.

[0130] According to different power requirements, the number of battery monomers 20 can be set to any value. The plurality of battery monomers 20 can be connected in series, parallel or hybrid manner to achieve larger capacity or power. Since the number of battery monomers 20 included in each battery device 10 can be large, in order to facilitate installation, the battery monomers 20 can be arranged in groups, and each group of battery monomers 20 forms a battery module. The number of battery monomers 20 included in the battery module is not limited and can be set according to requirements.

[0131] In the embodiments of the present application, according to different power requirements, the number of battery monomers 20 can be set to any value. The plurality of battery monomers 20 can be connected in series, parallel or hybrid manner to achieve larger capacity or power. Since the number of battery monomers 20 included in each battery device 10 can be large, in order to facilitate installation, the battery monomers 20 can be arranged in groups, and each group of battery monomers 20 forms a battery module. The number of battery monomers 20 included in the battery module is not limited and can be set according to requirements. The battery device 10 can include a plurality of battery modules, and these battery modules can be connected in series, parallel or hybrid manner.

[0132] Figure 3A structural diagram of a battery cell 20 is shown, Figure 4 A structural diagram of a battery cell 20 is shown, Figure 3 Figure 4 As shown in FIGS. 1 and 2, the battery cell 20 can include a housing 21 having a closed accommodation space and an electrode assembly 22 disposed in the accommodation space of the housing 21. The housing 21 can include a shell 211 having at least one opening and an end cover 212 for being coupled with the shell 211 to form the housing 21 having the closed accommodation space.

[0133] It should be understood that the battery cell 20 in the embodiments of the present application can be a secondary battery, which refers to a battery cell 20 that can be activated by charging after discharging. For example, the battery cell 20 can be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel-hydrogen battery, a nickel-cadmium battery, a lead-acid battery, etc.

[0134] The electrode assembly 22 in the embodiments of the present application includes a positive electrode, a negative electrode, and a separator disposed between the negative electrode and the positive electrode. During the charging and discharging of the battery cell 20, active ions (e.g., lithium ions) are inserted and extracted between the positive electrode and the negative electrode. The separator disposed between the positive electrode and the negative electrode can prevent the positive and negative electrodes from short-circuiting while allowing the active ions to pass through.

[0135] In some embodiments, the end cover 212 can be a plate-shaped structure for covering the opening of the shell 211. In other embodiments, the end cover 212 has a similar structure to the shell 211, i.e., both the shell 211 and the end cover 212 are hollow structures having one opening. The two openings are butted to form the housing 21 having the closed accommodation space.

[0136] It should be understood that if the end cover 212 is a plate-shaped structure, the shell 211 can be a hollow structure having one or more openings. For example, if the shell 211 is a hollow structure having one opening at one end, the end cover 212 can be one. If the shell 211 is a hollow structure having openings at opposite ends, the end cover 212 can be two, each covering an opening at one end of the shell 211.

[0137] The housing 21 can have various shapes, such as a cylinder, a cuboid, or other polyhedrons. For example, Figure 3 Figure 4 As shown in FIGS. 1 and 2, the battery cell 20 can include a housing 21 having a closed accommodation space and an electrode assembly 22 disposed in the accommodation space of the housing 21. The housing 21 can include a shell 211 having at least one opening and an end cover 212 for being coupled with the shell 211 to form the housing 21 having the closed accommodation space.

[0138] ​​It should be understood that the end cover 212 of the embodiments of the present application is used to cooperate with the shell 211 to isolate the internal environment of the battery monomer 20 from the external environment. The shape of the end cover 212 can be adapted to the shape of the shell 211, as shown in Figure 3 and Figure 4 The shell 211 is a cuboid structure and the end cover 212 is a rectangular plate structure adapted to the shell 211.

[0139] In some embodiments, the shell 211 can be a hollow structure with an opening formed at least at one end, and the shape of the end cover 212 can be adapted to the shape of the shell 211, and the end cover 212 is used to cover the opening of the shell 211, so that the shell 21 isolates the internal environment of the battery monomer 20 from the external environment. If the shell 211 is a hollow structure with an opening formed at one end, the end cover 212 can be provided as one.

[0140] The material of the shell 211 of the embodiments of the present application can include one or more, such as copper, iron, aluminum, steel, aluminum alloy, etc. The material of the end cover 212 can also be one or more, such as copper, iron, aluminum, steel, aluminum alloy, etc. Among them, the material of the end cover 212 and the material of the shell 211 can be the same or different; the materials of different walls of the shell 211 can also be the same or different.

[0141] The end cover 212 of the embodiments of the present application can be any wall of the shell 21, for example, the end cover 212 can be the largest wall among the multiple walls included in the shell 21, or the smallest wall, or it can also be other walls, and the embodiments of the present application are not limited thereto. Or, the end cover 212 can also be other structures, for example, the end cover 212 can also be a groove structure with an opening to cover the opening of the shell 211, and the embodiments of the present application are not limited thereto.

[0142] It should be understood that the battery monomer 20 also includes an electrode terminal 214. The electrode terminal 214 of the embodiments of the present application is used to be electrically connected with the electrode assembly 22 inside the battery monomer 20 to output the electric energy of the battery monomer 20. As shown in Figure 3 to Figure 4As shown, the battery cell 20 can include at least two electrode terminals 214, which can include at least one positive electrode terminal 214a and at least one negative electrode terminal 214b, the positive electrode terminal 214a being configured to be electrically connected to the positive electrode tab 222a of the electrode assembly 22, and the negative electrode terminal 214b being configured to be electrically connected to the negative electrode tab 222b of the electrode assembly 22. The positive electrode terminal 214a can be directly connected to the positive electrode tab 222a, or can be indirectly connected to the positive electrode tab 222a, and the negative electrode terminal 214b can be directly connected to the negative electrode tab 222b, or can be indirectly connected to the negative electrode tab 222b. For example, the positive electrode terminal 214a can be electrically connected to the positive electrode tab 222a through a connecting member 23, and the negative electrode terminal 214b can be electrically connected to the negative electrode tab 222b through a connecting member 23. It should be understood that, in the embodiments of the present application, the positive electrode tab 222a and the negative electrode tab 222b can be collectively referred to as a tab 222.

[0143] In the embodiments of the present application, the walls of the shell 211 and the walls of the end cover 212 are collectively referred to as the walls of the battery cell 20, wherein the walls of the shell 211 include a bottom wall and four side walls for the cuboid-shaped battery cell 20 shown in FIGS. 1 to 3. Figure 3 and Figure 4 For the cuboid-shaped battery cell 20 shown in FIGS. 1 to 3, the walls of the shell 211 include a bottom wall and four side walls. The shell 211 is determined according to the shape of the combined one or more electrode assemblies 22, for example, the shell 211 can be a hollow cuboid or a square or a cylinder, and one of the faces of the shell 211 has an opening so that the one or more electrode assemblies 22 can be placed in the shell 211. For example, when the shell 211 is a hollow cuboid or a square, one of the planes of the shell 211 is an open plane, i.e., the plane does not have a wall so that the inside and outside of the shell 211 are in communication. When the shell 211 can be a hollow cylinder, the end face of the shell 211 is an open plane, i.e., the end face does not have a wall so that the inside and outside of the shell 211 are in communication. The end cover 212 covers the opening and is connected to the shell 211 to form a closed cavity in which the electrode assembly 22 is placed. The shell 211 is filled with an electrolyte, for example, an electrolyte solution.

[0144] In the battery cell 20, the electrode assembly 22 is a component in which an electrochemical reaction occurs in the battery cell 20, and according to actual use requirements, the electrode assembly 22 in the shell 211 can be one or multiple. For example, as shown in FIGS. 1 to 3, two electrode assemblies 22 are provided in the battery cell 20. The electrode assembly 22 can be a cylinder, a cuboid, etc. If the electrode assembly 22 is a cylindrical structure, the shell 211 can also be a cylindrical structure, and if the electrode assembly 22 is a cuboid structure, the shell 211 can also be a cuboid structure. Figure 4

[0145] ​In the battery cell 20, the electrode assembly 22 is a component in which electrochemical reactions occur in the battery cell 20, and the electrode assembly 22 in the housing 211 can be one or multiple according to actual use requirements. For example, as shown in Figure 4 two electrode assemblies 22 are arranged in the battery cell 20. The electrode assembly 22 can be a cylinder, a cuboid, etc., and if the electrode assembly 22 is a cylinder structure, the housing 211 can also be a cylinder structure, and if the electrode assembly 22 is a cuboid structure, the housing 211 can also be a cuboid structure. In the embodiment of the present application, the material of the housing 211 can include the following materials: copper, iron, aluminum, steel, aluminum alloy, etc.

[0146] The battery cell 20 can also be provided with a pressure relief mechanism 213. The pressure relief mechanism 213 is used to actuate to release the internal pressure or temperature when the internal pressure or temperature of the battery cell 20 reaches a threshold value.

[0147] The pressure relief mechanism 213 arranged on the battery cell 20 can be various possible pressure relief mechanisms 213. For example, the pressure relief mechanism 213 can be a temperature-sensitive pressure relief mechanism configured to be able to melt when the internal temperature of the battery cell 20 provided with the pressure relief mechanism 213 reaches a threshold value; and / or, the pressure relief mechanism 213 can be a pressure-sensitive pressure relief mechanism configured to be able to break when the internal air pressure of the battery cell 20 provided with the pressure relief mechanism 213 reaches a threshold value.

[0148] In some implementations, the battery cell 20 can also be provided with an insulating piece arranged in the receiving space of the housing 211, and the insulating piece can be a hollow structure with one end or multiple ends forming an opening, and the receiving space in the hollow structure is used to accommodate the electrode assembly 22 to improve the insulation performance of the battery cell 20.

[0149] Figure 5 A cross-sectional schematic view of the battery cell 20 provided by an embodiment of the present application is shown. Figure 6 A partially enlarged cross-sectional schematic view of the battery cell 20 provided by an embodiment of the present application is shown. Figure 7 A cross-sectional schematic view of the first sealing structure 50 provided by another embodiment of the present application is shown. Figure 8 A partially enlarged cross-sectional schematic view of the battery cell 20 provided by another embodiment of the present application is shown. Figure 6 The first wall 215 in the battery cell 20 is provided with the first sealing structure 50. Figure 7 may be Figure 6 or Figure 5 A cross-sectional schematic view of the first sealing structure 50 is shown. Figure 8 An enlarged cross-sectional schematic view of the area of the liquid injection hole 216 of the battery cell 20 without assembling the first sealing structure 50 and the second sealing structure 60 is shown.

[0150] In some implementations, such as Figure 4 to Figure 8 As shown, the battery cell 20 includes: a housing 21, an electrode assembly 22, and a first sealing structure 50. The housing 21 includes a first wall 215, and the first wall 215 is provided with a liquid injection hole 216 extending through the first wall 215 along a first direction. The electrode assembly 22 is housed inside the housing 21. The first sealing structure 50 is sealed to the liquid injection hole 216. The first sealing structure 50 includes a groove 510 with its opening facing away from the electrode assembly 22. The maximum outer diameter of the portion of the first sealing structure 50 other than the groove 510 is less than or equal to the minimum inner diameter of the liquid injection hole 216. The maximum outer diameter of the portion of the first sealing structure 50 including the groove 510 is greater than the minimum inner diameter of the liquid injection hole 216. The first direction is along the thickness of the first wall 215 and toward the electrode assembly 22.

[0151] For example, such as Figure 8 As shown, the minimum inner diameter of the injection hole 216 in this embodiment can be represented by D4.

[0152] It should be understood that the outer casing 21 in this embodiment may include a housing 211 and an end cap 212. The housing 211 is a hollow structure with at least one opening, and the end cap 212 is used to fasten with the housing 211 to form an outer casing 21 with a closed receiving space. For example, as shown... Figure 3 to Figure 5 As shown, when the first wall 215 is an end cap 212, the injection hole 216 can be provided on the end cap 212, and the first sealing structure 50 is sealed to the injection hole 216. Alternatively, the first wall 215 can be the housing 211 of the battery cell 20, meaning the injection hole 216 can be provided on any wall of the housing 211, such as the wall with the largest area, and the first sealing structure 50 is sealed to the injection hole 216.

[0153] It should also be understood that in some implementations, the liquid injection hole 216 may be located on the same wall of the housing 21 as the pressure relief mechanism 213 of the battery cell 20, or the liquid injection hole 216 and the pressure relief mechanism 213 of the battery cell 20 may be located on different walls of the housing 21.

[0154] It should also be understood that the sealing connection between the first sealing structure 50 and the injection hole 216 in the embodiments of this application can refer to an interference fit or a snap-fit ​​connection between the first sealing structure 50 and the inner wall of the injection hole 216.

[0155] It should also be understood that the first direction in the embodiments of this application refers to the direction along the thickness of the first wall 215 and toward the electrode assembly 22. In some implementations, the first direction may also refer to the assembly direction of the first sealing structure 50.

[0156] It should also be understood that the cross-sectional shape of the liquid injection hole 216 in the plane perpendicular to the first direction in the embodiments of the present application can be circular, oval, polygonal, or the like. Specifically, the cross-sectional shape of the liquid injection hole 216 in the plane perpendicular to the first direction can be set according to actual needs.

[0157] It should also be understood that the maximum outer diameter of the part of the first sealing structure 50 other than the groove 510 being less than or equal to the minimum inner diameter D4 of the liquid injection hole 216 can mean that the maximum outer diameter of the solid area of the part of the first sealing structure 50 other than the groove 510 is less than or equal to the minimum inner diameter D4 of the liquid injection hole 216, so that the first sealing structure 50 can enter the liquid injection hole 216 under the action of pressure, so that at least part of the first sealing structure 50 is accommodated in the liquid injection hole 216.

[0158] It should also be understood that the maximum outer diameter of the part of the first sealing structure 50 including the groove 510 being greater than the minimum inner diameter D4 of the liquid injection hole 216 can mean that the maximum outer diameter of the part of the first sealing structure 50 other than the groove 510 in the plane perpendicular to the first direction is greater than the minimum inner diameter D4 of the liquid injection hole 216, so as to limit the first sealing structure 50, reducing the risk of the first sealing structure 50 falling or falling off into the inside of the battery monomer 20.

[0159] It should also be understood that the material of the first sealing structure 50 in the embodiments of the present application includes but is not limited to at least one of the following: fluororubber, ternary ethylene-propylene rubber, binary ethylene-propylene rubber, polytetrafluoroethylene plastic.

[0160] In the embodiments of the present application, by providing the first sealing structure 50 in the battery monomer 20, and the first sealing structure 50 includes the groove 510 with the opening away from the electrode assembly 22, the maximum outer diameter of the part of the first sealing structure 50 other than the groove 510 is less than or equal to the minimum inner diameter D4 of the liquid injection hole 216, and the maximum outer diameter of the part of the first sealing structure 50 including the groove 510 is greater than the minimum inner diameter D4 of the liquid injection hole 216, compared with the solid sealing structure in the prior art, so as to facilitate the sealing connection between the first sealing structure 50 and the liquid injection hole 216 while assembling the first sealing structure 50 to the liquid injection hole 216, facilitate the assembly of the first sealing structure 50, improve the sealing effect of the liquid injection hole 216 of the battery monomer 20, thereby improving the use performance and assembly performance of the battery monomer 20.

[0161] In some implementations, as Figure 4 to Figure 8As shown, the first sealing structure 50 includes a first portion 520 and a second portion 530 distributed along the first direction. The second portion 530 is located on the side of the first portion 520 facing the electrode assembly 22. The first portion 520 includes a through hole 521 extending through the first portion 520 along the first direction. The second portion 530 includes a countersunk hole 531 facing away from the electrode assembly 22. The through hole 521 communicates with the countersunk hole 531 to form the groove 510. At least a portion of the second portion 530 is accommodated in the injection hole 216 and is sealed to the injection hole 216. The maximum inner diameter of the countersunk hole 531 is greater than the maximum inner diameter of the through hole 521. The maximum outer diameter of the second portion 530 is less than or equal to the minimum inner diameter D4 of the injection hole 216.

[0162] It should be understood that the second portion 530 being located on the side of the first portion 520 facing the electrode assembly 22 can mean that the second portion 530 is connected to the side of the first portion 520 facing the electrode assembly 22, and the second portion 530 and the first portion 520 can be integrally formed or separately formed. For example, the second portion 530 and the first portion 520 can be manufactured by compression molding, thermoforming, or injection molding.

[0163] It should also be understood that, such as Figure 7 As shown, the maximum inner diameter of the through hole 521 can be represented by D1, the maximum inner diameter of the countersunk hole 531 can be represented by D2, and the maximum outer diameter of the second part 530 can be represented by D3.

[0164] It should also be understood that the shape of the cross-section of the through hole 521 in the embodiment of this application on the plane perpendicular to the first direction can be set as a circle, an ellipse or a polygon, etc., and the shape of the cross-section of the countersunk hole 531 in the embodiment of this application on the plane perpendicular to the first direction can be set as a circle, an ellipse or a polygon, etc. Specifically, the shape of the cross-section of the through hole 521 and the countersunk hole 531 on the plane perpendicular to the first direction can be set according to actual needs.

[0165] It should also be understood that the maximum inner diameter D2 of the countersunk hole 531 is greater than the maximum inner diameter D1 of the through hole 521, and the maximum outer diameter D3 of the second portion 530 is less than or equal to the minimum inner diameter of the injection hole 216. This can mean that the second portion 530 can enter the injection hole 216 under pressure, at least a portion of the second portion 530 is accommodated in the injection hole 216, and the first portion 520 serves to limit the first sealing structure 50, thereby reducing the risk of the first sealing structure 50 falling or detaching into the battery cell 20. For example, the maximum outer diameter D3 of the second portion 530 can refer to the maximum outer diameter of the solid area of ​​the second portion 530 excluding the countersunk hole 531.

[0166] In the embodiment of the present application, by setting the first sealing structure 50 to include a first portion 520 and a second portion 530 distributed along the first direction, the second portion 530 is located on the side of the first portion 520 facing the electrode assembly 22, and the first portion 520 is set to include a through hole 521 penetrating through the first portion 520 along the first direction, the second portion 530 is set to include a counterbore 531 facing away from the electrode assembly 22, the through hole 521 and the counterbore 531 communicate to form the groove 510, at least part of the second portion 530 is accommodated in the liquid injection hole 216 and sealingly connected with the liquid injection hole 216, the maximum inner diameter D2 of the counterbore 531 is greater than the maximum inner diameter D1 of the through hole 521, and the maximum outer diameter D3 of the second portion 530 is less than or equal to the minimum inner diameter D4 of the liquid injection hole 216, that is, at least part of the second portion 530 can be smoothly accommodated in the liquid injection hole 216 and sealingly connected with the liquid injection hole 216 during the assembly of the first sealing structure 50 to the liquid injection hole 216, and the first portion 520 can limit the first sealing structure 50 to reduce the risk of the first sealing structure 50 falling or falling into the inside of the battery monomer 20, thereby improving the assembly performance and use performance of the battery monomer 20, and the structure design is simple, facilitating the processing and manufacturing of the battery monomer 20.

[0167] In some implementations, as shown in Figure 7 and Figure 8 the difference between the maximum outer diameter D3 of the second portion 530 and the minimum inner diameter of the counterbore 531 is less than the minimum inner diameter D4 of the liquid injection hole 216. For example, as shown in Figure 8 the minimum inner diameter of the counterbore 531 can be represented as d2.

[0168] In the embodiment of the present application, by setting the difference between the maximum outer diameter D3 of the second portion 530 and the minimum inner diameter d2 of the counterbore 531 to be less than the minimum inner diameter D4 of the liquid injection hole 216, at least part of the second portion 530 can be smoothly accommodated in the liquid injection hole 216 during the assembly of the first sealing structure 50, reducing the force applied to the first sealing structure 50 during assembly, thereby improving the assembly performance and use performance of the battery monomer 20.

[0169] In some implementations, as shown in Figure 7 and Figure 8As shown, the difference between the maximum outer diameter D5 of the first portion 520 and the maximum inner diameter D1 of the through hole 521 is greater than the minimum inner diameter D4 of the liquid injection hole 216. In this way, in the embodiments of the present application, by setting the difference between the maximum outer diameter D5 of the first portion 520 and the maximum inner diameter D1 of the through hole 521 to be greater than the minimum inner diameter D4 of the liquid injection hole 216, in the case that at least part of the second portion 530 is accommodated in the liquid injection hole 216 during assembly of the first sealing structure 50, the first portion 520 can effectively play a limiting role for the first sealing structure 50, so as to further reduce the risk of the first sealing structure 50 falling off or falling into the inside of the battery monomer 20, thereby improving the assembly performance and use performance of the battery monomer 20.

[0170] In some implementations, as Figure 4 to Figure 7 As shown, the first sealing structure 50 further includes a third portion 540 arranged on the side of the second portion 530 facing the electrode assembly 22, and the projection of the second portion 530 covers the projection of the third portion 540 in the plane perpendicular to the first direction, and the outer diameter of the third portion 540 gradually decreases along the first direction.

[0171] It should be understood that the third portion 540 can be connected to the surface of the second portion 530 facing the electrode assembly 22, and the third portion 540 and the second portion 530 can be integrally formed or separately formed. For example, the first portion 520, the second portion 530 and the third portion 540 can be integrally injection molded.

[0172] It should be further understood that the projection of the second portion 530 covers the projection of the third portion 540, and the outer diameter of the third portion 540 gradually decreases along the first direction, so as to facilitate the assembly of the first sealing structure 50, reduce the influence of the third portion 540 on the first sealing structure 50, and reduce the pressure applied to the first sealing structure 50 during assembly. It should be further understood that the gradual decrease of the outer diameter of the third portion 540 along the first direction can mean that the outer diameter of the third portion 540 decreases linearly and continuously along the first direction, or discontinuously, for example, the third portion 540 can be arranged in a circular truncated cone structure or a prismatic truncated cone structure. It should be further understood that the third portion 540 can be arranged in a solid structure, a hollow structure or a groove structure with an opening at one end, and specifically, the structure of the third portion 540 can be arranged according to actual needs.

[0173] In the embodiments of the present application, by setting the first sealing structure 50 to include a third portion 540 connected to the second portion 530 on the side facing the electrode assembly 22, and in a plane perpendicular to the first direction, the projection of the second portion 530 covers the projection of the third portion 540, and along the first direction, the outer diameter of the third portion 540 gradually decreases, so as to smoothly accommodate the portion of the first sealing structure 50 inside the liquid injection hole 216, effectively reducing the force applied to the first sealing structure 50 during assembly, thereby improving the assembly performance and use performance of the battery monomer 20.

[0174] In some implementations, as shown in FIG. 6, the surface of the first sealing structure 50 on the side away from the electrode assembly 22 is lower than the surface of the first wall 215 on the side away from the electrode assembly 22, or the surface of the first sealing structure 50 on the side away from the electrode assembly 22 is flush with the surface of the first wall 215 on the side away from the electrode assembly 22. Figure 4 to 6

[0175] In the embodiments of the present application, by setting the surface of the first sealing structure 50 on the side away from the electrode assembly 22 to be lower than the surface of the first wall 215 on the side away from the electrode assembly 22, or setting the surface of the first sealing structure 50 on the side away from the electrode assembly 22 to be flush with the surface of the first wall 215 on the side away from the electrode assembly 22, to reduce the collision or wear of the first sealing structure 50 during assembly or movement of the battery monomer 20, improve the sealing performance of the first sealing structure 50, thereby improving the use performance of the battery monomer 20.

[0176] In some implementations, along the first direction, the inner diameter of the liquid injection hole 216 gradually decreases.

[0177] It should be understood that the inner diameter of the liquid injection hole 216 along the first direction can continuously decrease or non-continuously decrease. For example, as shown in FIG. 6, the inner diameter of the liquid injection hole 216 along the first direction can non-continuously decrease, the liquid injection hole 216 can include two hole sections, and the hole diameter of the hole section close to the electrode assembly 22 is smaller than the hole diameter of the hole section away from the electrode assembly 22. Figure 8

[0178] In the embodiments of the present application, by setting the inner diameter of the liquid injection hole 216 along the first direction to gradually decrease, during the assembly of the first sealing structure 50, the structure of the liquid injection hole 216 can effectively limit the first sealing structure 50, to further reduce the risk of the first sealing structure 50 falling off or falling into the inside of the battery monomer 20, thereby improving the assembly performance and use performance of the battery monomer 20, and the structural design of the liquid injection hole 216 is simple, facilitating the processing and manufacturing of the battery monomer 20.​​

[0179] In some implementations, the first portion 520 is integrally formed with the second portion 530. For example, the first portion 520 and the second portion 530 can be integrally formed by molding, thermoforming or injection molding.

[0180] In the embodiments of the present application, by integrally forming the first portion 520 and the second portion 530, the sealing performance and the assembly performance of the first sealing structure 50 can be effectively improved, so as to improve the use performance of the battery monomer 20, and meanwhile, the processing and manufacturing costs of the battery monomer 20 can be reduced.

[0181] Figure 9 A partial enlarged sectional view of a battery monomer 20 provided by another embodiment of the present application is shown.

[0182] In some implementations, as shown in Figure 9 The battery monomer 20 further includes a second sealing structure 60, the second sealing structure 60 is sealingly connected with the liquid injection hole 216, the second sealing structure 60 is located on the side of the first sealing structure 50 away from the electrode assembly 22, the second sealing structure 60 is fixedly connected with the first sealing structure 50, and the projection of the second sealing structure 60 covers the projection of the first sealing structure 50 in a plane perpendicular to the first direction.

[0183] It should be understood that the second sealing structure 60 in the embodiments of the present application is sealingly connected with the liquid injection hole 216, which means that part of the second sealing structure 60 is weldingly or adhesively connected with part of the inner wall of the liquid injection hole 216, so as to achieve the sealing assembly between the second sealing structure 60 and the liquid injection hole 216.

[0184] It should be further understood that the fixed connection between the second sealing structure 60 and the first sealing structure 50 can be a clamping connection, an interference fit or a threaded connection.

[0185] It should be further understood that the second sealing structure 60 in the embodiments of the present application can be fixedly connected with the first sealing structure 50 and then assembled to the liquid injection hole 216, or the first sealing structure 50 can be assembled to the liquid injection hole 216 first, and then the second sealing structure 60 is fixedly connected with the first sealing structure 50.

[0186] It should be further understood that the material of the second sealing structure 60 includes but is not limited to aluminum material, steel material or titanium alloy, etc. For example, the material of the second sealing structure 60 can be the same as the material of the shell 211 of the battery monomer 20.

[0187] In the embodiment of the present application, by arranging the second sealing structure 60 in the battery monomer 20, the second sealing structure 60 is sealingly connected with the liquid injection hole 216, the second sealing structure 60 is located on the side of the first sealing structure 50 away from the electrode assembly 22, and in the plane perpendicular to the first direction, the projection of the second sealing structure 60 covers the projection of the first sealing structure 50, thereby further improving the limiting effect of the first sealing structure 50, further reducing the risk of the first sealing structure 50 falling off or falling into the inside of the battery monomer 20, thereby improving the assembly performance and use performance of the battery monomer 20, and at the same time, the second sealing structure 60 is fixedly connected with the first sealing structure 50, which can improve the assembly efficiency of the first sealing structure 50 and the second sealing structure 60 relative to the liquid injection hole 216.

[0188] In some implementations, as shown in Figure 8 The second sealing structure 60 includes a main body part 610 and a protruding part 620, the protruding part 620 is arranged on the surface of the main body part 610 on the side facing the electrode assembly 22, and the protruding part 620 is connected with the inner wall of the groove 510 by one of the following connection modes: threaded connection, clamping connection or interference fit.

[0189] It should be understood that the main body part 610 and the protruding part 620 in the embodiment of the present application can be integrally formed or separately formed. In the case of separately forming the main body part 610 and the protruding part 620 in the second sealing structure 60, the main body part 610 and the protruding part 620 can be connected by welding.

[0190] It should also be understood that the protruding part 620 and the inner wall of the groove 510 are connected by one of the following connection modes: threaded connection, clamping connection or interference fit, which means that the protruding part of the second sealing structure 60 and the inner wall of the groove 510 of the first sealing structure 50 are first fixedly connected by threaded connection, clamping connection or interference fit, and then assembled to the liquid injection hole 216.

[0191] In the embodiment of the present application, by arranging the second sealing structure 60 to include a main body part 610 and a protruding part 620, and the protruding part 620 is arranged on the surface of the main body part 610 on the side facing the electrode assembly 22, and the protruding part 620 is connected with the inner wall of the groove 510 by one of the following connection modes: threaded connection, clamping connection or interference fit, the connection strength between the second sealing structure 60 and the first sealing structure 50 is improved, so as to effectively improve the assembly efficiency of the second sealing structure 60 and the first sealing structure 50 relative to the liquid injection hole 216, thereby effectively improving the limiting effect of the first sealing structure 50, reducing the risk of the first sealing structure 50 falling off or falling into the inside of the battery monomer 20, thereby improving the assembly performance and use performance of the battery monomer 20.

[0192] In some implementations, the protrusion 620 is threadedly connected with the inner wall of the through hole 521. For example, the outer periphery of the protrusion 620 of the second sealing structure 60 can be provided with external threads, and the inner wall of the first sealing structure 50 can be provided with internal threads matched with the external threads, so as to achieve the threaded connection between the protrusion 620 and the inner wall of the through hole 521.

[0193] In the embodiments of the present application, the threaded connection between the protrusion 620 and the inner wall of the through hole 521 improves the assembly efficiency of the second sealing structure 60 and the first sealing structure 50 relative to the liquid injection hole 216, thereby effectively improving the limiting effect of the first sealing structure 50, further reducing the risk of the first sealing structure 50 falling off or falling into the inside of the battery monomer 20, thereby improving the assembly performance and use performance of the battery monomer 20, and the connection method is simple and efficient, which facilitates reducing the processing and manufacturing cost of the battery monomer 20.

[0194] In some implementations, as shown in Figure 8 and Figure 9 The liquid injection hole 216 includes a first hole section 217 and a second hole section 218 distributed along the first direction, the first hole section 217 is located on the side of the second hole section 218 away from the electrode assembly 22, the hole diameter of the first hole section 217 is greater than that of the second hole section 218, part of the second sealing structure 60 is accommodated in the first hole section 217, and at least part of the first sealing structure 50 is accommodated in the second hole section 218.

[0195] It should be understood that, in the embodiments of the present application, the hole diameter of the first hole section 217 is greater than that of the second hole section 218, which can mean that the average hole diameter of the first hole section 217 is greater than that of the second hole section 218, or the maximum hole diameter of the first hole section 217 is greater than that of the second hole section 218, or the minimum hole diameter of the first hole section 217 is greater than that of the second hole section 218.

[0196] It should also be understood that the cross-sectional shape of the first hole section 217 and the second hole section 218 in the plane perpendicular to the first direction in the embodiments of the present application can be set according to actual needs. For example, the cross-sectional shape of the first hole section 217 and the second hole section 218 in the plane perpendicular to the first direction can be circular, elliptical or polygonal, etc.

[0197] In this embodiment of the application, by providing a first hole segment 217 and a second hole segment 218 distributed along the first direction in the injection hole 216, and the diameter of the first hole segment 217 being larger than the diameter of the second hole segment 218, a portion of the second sealing structure 60 is accommodated in the first hole segment 217, and at least a portion of the first sealing structure 50 is accommodated in the second hole segment 218, so as to improve the assembly efficiency of the second sealing structure 60 and the first sealing structure 50 relative to the injection hole 216, thereby improving the assembly performance and performance of the battery cell 20.

[0198] Figure 10 A partially enlarged cross-sectional schematic diagram of a battery cell 20 provided in another embodiment of this application is shown.

[0199] In some implementations, such as Figure 10 As shown, the injection hole 216 also includes a straight section 219 disposed between the first hole section 217 and the second hole section 218. The first sealing structure 50 also includes an extension 550 disposed on the outer periphery of the first sealing structure 50. The extension 550 extends in a direction away from the geometric center of the first sealing structure 50. The surface of the extension 550 facing the electrode assembly 22 is attached to the surface of the straight section 219 facing away from the electrode assembly 22.

[0200] It should be understood that the straight section 219 disposed between the first hole segment 217 and the second hole segment 218 in the embodiments of this application can refer to the straight section 219 being connected between the first hole segment 217 and the second hole segment 218, and the straight section 219 can be integrally formed with the first hole segment 217 and the second hole segment 218 or formed separately.

[0201] It should also be understood that the extension 550 provided on the outer periphery of the first sealing structure 50 can mean that the extension 550 can be integrally formed with the first sealing structure 50 or separately formed. For example, when the extension 550 can be integrally formed with the first sealing structure 50, the extension 550 can be integrally injection molded with the first sealing structure 50.

[0202] It should also be understood that the attachment of the surface of the extension 550 facing the electrode assembly 22 to the surface of the straight section 219 facing away from the electrode assembly 22 can mean that the surface of the extension 550 facing the electrode assembly 22 is in direct contact with the surface of the straight section 219 facing away from the electrode assembly 22.

[0203] In the embodiment of the present application, by arranging the flat section 219 between the first hole section 217 and the second hole section 218 of the liquid injection hole 216, the first sealing structure 50 further comprises an extension 550 arranged on the outer periphery of the first sealing structure 50, the extension 550 extends away from the geometric center of the first sealing structure 50, and the surface of the extension 550 on the side facing away from the electrode assembly 22 is attached to the surface of the flat section 219 on the side facing away from the electrode assembly 22, so as to improve the limiting effect of the first sealing structure 50, further reduce the risk of the first sealing structure 50 falling off or falling into the inside of the battery monomer 20, thereby improving the assembly performance and use performance of the battery monomer 20.

[0204] In some implementations, along the first direction, the size of the protruding portion 620 is less than or equal to the depth of the groove 510. For example, as shown in Figure 9 and Figure 10 , the depth of the groove 510 can be represented by L1, and the size of the protruding portion 620 can be represented by L2.

[0205] It should also be understood that the size L2 of the protruding portion 620 is less than or equal to the depth L1 of the groove 510, which means that the surface of the first body portion 610 on the side facing the electrode assembly 22 can be attached or directly contacted with the surface of the extension 550 on the side facing away from the electrode assembly 22, thereby improving the connection strength between the first sealing structure 50 and the second sealing structure 60, and at the same time reducing the thickness of the first sealing structure 50 and the second sealing structure 60 in the first direction after being fixedly connected.

[0206] In the embodiment of the present application, by setting the size L2 of the protruding portion 620 to be less than or equal to the depth L1 of the groove 510, the protruding portion 620 can be accommodated in the groove 510, that is, the surface of the first body portion 610 on the side facing the electrode assembly 22 can be attached with the surface of the extension 550 on the side facing away from the electrode assembly 22, thereby improving the connection strength between the first sealing structure 50 and the second sealing structure 60, facilitating the assembly efficiency of the second sealing structure 60 and the first sealing structure 50 relative to the liquid injection hole 216, thereby improving the assembly performance and use performance of the battery monomer 20.

[0207] In some implementations, the surface of the second sealing structure 60 on the side facing away from the electrode assembly 22 is lower than the surface of the first wall 215 on the side facing away from the electrode assembly 22, or the surface of the second sealing structure 60 on the side facing away from the electrode assembly 22 is flush with the surface of the first wall 215 on the side facing away from the electrode assembly 22.

[0208] In the embodiments of the present application, by arranging the surface of the side of the second sealing structure 60 facing away from the electrode assembly 22 to be lower than the surface of the side of the first wall 215 facing away from the electrode assembly 22, or the surface of the side of the second sealing structure 60 facing away from the electrode assembly 22 to be flush with the surface of the side of the first wall 215 facing away from the electrode assembly 22, the collision or abrasion of the battery monomer 20 to the second sealing structure 60 during assembly or movement is reduced, the sealing performance of the second sealing structure 60 is improved, and thus the use performance of the battery monomer 20 is improved.

[0209] According to some embodiments of the present application, the embodiments of the present application further provide a battery device 10 comprising a plurality of battery monomers 20, the battery monomer 20 being the battery monomer 20 in any of the above embodiments.

[0210] According to some embodiments of the present application, the embodiments of the present application further provide a battery device 10 comprising a plurality of battery monomers 20, the battery monomer 20 being the battery monomer 20 in any of the above embodiments. Figure 1 The vehicle 1 shown can also be any electric device using the battery device 10.

[0211] The electric device can be any of the above-mentioned devices or systems using the battery device 10.

[0212] According to some embodiments of the present application, the embodiments of the present application further provide a battery device 10 comprising a plurality of battery monomers 20, the battery monomer 20 being the battery monomer 20 in any of the above embodiments.

[0213] According to some embodiments of the present application, referring to Figure 5 to Figure 8The battery cell 20 includes a housing 21, an electrode assembly 22, and a first sealing structure 50. The housing 21 includes a first wall 215 provided with a liquid injection hole 216 penetrating the first wall 215 in a first direction. The electrode assembly 22 is accommodated in an interior of the housing 21. The first sealing structure 50 is in sealing connection with the liquid injection hole 216. The first sealing structure 50 includes a groove 510 opening away from the electrode assembly 22. A maximum outer diameter of a portion of the first sealing structure 50 other than the groove 510 is less than or equal to a minimum inner diameter of the liquid injection hole 216. A maximum outer diameter of a portion of the first sealing structure 50 including the groove 510 is greater than the minimum inner diameter D4 of the liquid injection hole 216. The first direction is a direction along a thickness of the first wall 215 and toward the electrode assembly 22. The first sealing structure 50 includes a first portion 520 and a second portion 530 distributed in the first direction. The second portion 530 is located on a side of the first portion 520 toward the electrode assembly 22. The first portion 520 includes a through hole 521 penetrating the first portion 520 in the first direction. The second portion 530 includes a counterbore 531 opening away from the electrode assembly 22. The through hole 521 and the counterbore 531 communicate to form the groove 510. At least a portion of the second portion 530 is accommodated in and in sealing connection with the liquid injection hole 216. A maximum inner diameter D2 of the counterbore 531 is greater than a maximum inner diameter D1 of the through hole 521. A maximum outer diameter D3 of the second portion 530 is less than or equal to the minimum inner diameter D4 of the liquid injection hole 216. A difference between the maximum outer diameter D3 of the second portion 530 and the minimum inner diameter of the counterbore 531 is less than the minimum inner diameter D4 of the liquid injection hole 216. A difference between the maximum outer diameter D5 of the first portion 520 and the maximum inner diameter D1 of the through hole 521 is greater than the minimum inner diameter D4 of the liquid injection hole 216.

[0214] Finally, it should be noted that the above-described embodiments are merely intended to illustrate the technical solutions of the present application, and are not intended to limit the present application; even though the present application has been described in detail with reference to the above-described embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the above-described embodiments, or equivalently replace some or all of the technical features thereof; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the claims and the specification of the present application. In particular, as long as there is no structural conflict, each technical feature mentioned in each embodiment can be combined in any manner. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized by, The application relates to a battery, comprising: a housing (21) comprising a first wall (215) provided with a liquid injection hole (216) penetrating through the first wall (215) in a first direction; an electrode assembly (22) accommodated in the interior of the housing (21); a first sealing structure (50) sealingly connected with the liquid injection hole (216), the first sealing structure (50) comprising a groove (510) with an opening facing away from the electrode assembly (22), the maximum outer diameter of the part of the first sealing structure (50) except the groove (510) being less than or equal to the minimum inner diameter of the liquid injection hole (216), and the maximum outer diameter of the part of the first sealing structure (50) including the groove (510) being greater than the minimum inner diameter of the liquid injection hole (216), the first direction being the direction along the thickness of the first wall (215) and towards the electrode assembly (22).

2. The battery cell of claim 1, wherein, The first sealing structure (50) comprises a first part (520) and a second part (530) distributed along the first direction, the second part (530) being located on the side of the first part (520) towards the electrode assembly (22), wherein the first part (520) comprises a through hole (521) penetrating through the first part (520) along the first direction, the second part (530) comprises a counterbore (531) facing away from the electrode assembly (22), the through hole (521) and the counterbore (531) communicate to form the groove (510), at least part of the second part (530) is accommodated in the liquid injection hole (216) and sealingly connected with the liquid injection hole (216), the maximum inner diameter of the counterbore (531) is greater than the maximum inner diameter of the through hole (521), and the maximum outer diameter of the second part (530) is less than or equal to the minimum inner diameter of the liquid injection hole (216).

3. The battery cell of claim 2, wherein, The difference between the maximum outer diameter of the second part (530) and the minimum inner diameter of the counterbore (531) is less than the minimum inner diameter of the liquid injection hole (216).

4. The battery cell of claim 2, wherein, The difference between the maximum outer diameter of the first part (520) and the maximum inner diameter of the through hole (521) is greater than the minimum inner diameter of the liquid injection hole (216).

5. The battery cell of claim 2, wherein, The first sealing structure (50) further comprises a third part (540) provided on the side of the second part (530) towards the electrode assembly (22), in a plane perpendicular to the first direction, the projection of the second part (530) covers the projection of the third part (540), and the outer diameter of the third part (540) gradually decreases along the first direction.

6. The battery cell of claim 2, wherein, The surface on the side of the first sealing structure (50) facing away from the electrode assembly (22) is lower than the surface on the side of the first wall (215) facing away from the electrode assembly (22), or the surface on the side of the first sealing structure (50) facing away from the electrode assembly (22) is flush with the surface on the side of the first wall (215) facing away from the electrode assembly (22).

7. The battery cell of claim 2, wherein, In the first direction, an inner diameter of the liquid injection hole (216) gradually decreases.

8. The battery cell of claim 2, wherein, The first portion (520) is integrally formed with the second portion (530).

9. The battery cell of any one of claims 2 to 8, wherein, The battery cell further comprises a second sealing structure (60) sealingly connected with the liquid injection hole, the second sealing structure (60) is located on a side of the first sealing structure (50) away from the electrode assembly (22), the second sealing structure (60) is fixedly connected with the first sealing structure (50), In a plane perpendicular to the first direction, a projection of the second sealing structure (60) covers a projection of the first sealing structure (50).

10. The battery cell of claim 9, wherein, The second sealing structure (60) comprises a main body portion (610) and a protruding portion (620), the protruding portion (620) is arranged on a surface of the main body portion (610) on a side facing the electrode assembly (22), the protruding portion (620) is connected with an inner wall of the groove (510) by one of the following connection modes: threaded connection, clamping connection or interference fit.

11. The battery cell of claim 10, wherein, The protruding portion (620) is threadedly connected with an inner wall of the through hole (521).

12. The battery cell of claim 10, wherein, The liquid injection hole (216) comprises a first hole section (217) and a second hole section (218) distributed along the first direction, the first hole section (217) is located on a side of the second hole section (218) away from the electrode assembly (22), a hole diameter of the first hole section (217) is larger than a hole diameter of the second hole section (218), a part of the second sealing structure (60) is accommodated in the first hole section (217), and at least a part of the first sealing structure (50) is accommodated in the second hole section (218).

13. The battery cell of claim 12, wherein, The liquid injection hole (216) further comprises a flat section (219) arranged between the first hole section (217) and the second hole section (218), and the first sealing structure (50) further comprises an extension portion (550) arranged on an outer periphery of the first sealing structure (50), the extension portion (550) extends away from a geometric center of the first sealing structure (50), and a surface of the extension portion (550) on a side facing the electrode assembly (22) is attached to a surface of the flat section (219) on a side away from the electrode assembly (22).

14. The battery cell of claim 13, wherein, In the first direction, a size of the protruding portion (620) is less than or equal to a depth of the groove (510).

15. The battery cell of claim 9, wherein, A surface of the second sealing structure (60) on a side away from the electrode assembly (22) is lower than a surface of the first wall (215) on a side away from the electrode assembly (22), or the surface of the second sealing structure (60) on the side away from the electrode assembly (22) is flush with the surface of the first wall (215) on the side away from the electrode assembly (22).

16. A battery device characterized by comprising: Comprise: A plurality of battery cells, the battery cell being the battery cell as claimed in any one of claims 1 to 15.

17. An electrical device, comprising: Comprise: The battery device as claimed in claim 16, the battery device being used to provide electric energy for the electric device.

18. An energy storage device, characterized by Comprise: The battery device of claim 16, the battery device for storing electrical energy for the energy storage device.

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